spritesmods

We love it when this happens. Sometimes we post about cool technology that companies are developing which might start an outcry of “not a hack” — but then, just sometimes, it still inspires a few readers. [Jeroen Domburg] — who everyone knows as [Sprite_TM] and is a judge for The Hackaday Prize] — saw a recent video about micro robots, a project funded by DARPA, and decided to try making his own.

We shared the original story a few months ago about these replicator like micro-robots, which can quite literally swarm over surfaces, use tools, and manufacture micro-sized parts. The robots themselves are actually just dumb little magnets — the magic is in the surface underneath them.

This sparked an interest in several people, and [Mike] made a very simple version of it, capable of 1-dimensional movement. This inspired [Sprite_TM] to step it up a notch, with his own 2-dimensional version. He’s designed his own PCB that allows him to run current in various directions through the traces of the board — this effectively allows him to control a small neodymium magnet to go whichever way he wants.

We love old display technology, like Nixie tubes, but they’re often difficult to work with because they require higher voltages than digital logic. Vacuum florescent displays (VFD) fall into this category. While not necessarily “old”, they are becoming far less common than LCDs. The main benefit of a VFD is that it actually produces light directly; it doesn’t require a backlight. You’ll find these displays on various players and appliances: CD, DVD, VCR, microwaves, stoves, car headunits, and others.

[Sprite_tm] had written off some VFDs, but recently revisited them with renewed interest. He started by testing what sort of voltage would be required to drive the display. It took 3V for the filament plus 15V to drive the grids. There are VFD controller chips available, but he wanted to get this working with what he had on hand. He had experience with older 40xx series logic, which can be powered by much higher voltages than 5V 74xx. His final schematic has three 4094 serial to parallel chips with an ATtiny2313 controller. A 5V power supply is dropped to 3V with diodes to drive the filament while a boost converter brings it up to 15V for the 4094s that switch the segments. While the code is specific to this display, it would be a great place to start your own project.